D3.423 - Cross-Reactivity Among Hymenoptera Venoms: A Case Study on Apis, Vespula, and Polistes Allergens
Background
Hymenoptera venom allergy is a significant cause of systemic reactions, with cross-reactivity between venoms posing challenges for diagnosis and treatment. This study investigates the allergenic profiles of Apis mellifera (honeybee), Vespula sp. (wasp), and Polistes dominula (paper wasp) venoms in a patient with systemic reactions to both bee and wasp stings.
Method
A 43-year-old female experienced delayed systemic reactions (hand edema, dizziness, and general malaise) 24 hours after stings by both Apis mellifera and Vespula sp.. No urticarial lesions or other symptoms were observed. The patient also reported persistent rhinitis and conjunctivitis unrelated to venom exposure. Skin tests revealed sensitization to Polistes dominula, with high IgE levels to bee and wasp venoms. Cross-reactivity markers, including CCD (cross-reactive carbohydrate determinants), were also positive.
Venom extracts from *Apis mellifera*, *Vespula sp.*, and *Polistes dominula* were analyzed using SDS-PAGE, Western blot, and ELISA to assess protein profiles, IgE reactivity, and antibody titers, with protein concentrations measured by the Bradford method.
Results
Western blot revealed strong IgE recognition of allergenic proteins across all three venoms, with significant cross-reactivity between Vespula and Polistes. Major recognized proteins included phospholipases (Api m 1, Ves v 1, Pol d 1) and hyaluronidases (Api m 2, Ves v 2, Pol d 2). The patient’s IgE also bound to proteins in the 30–45 kDa range, corresponding to shared venom components. ELISA titers confirmed low antibody levels, suggesting limited clinical reactivity despite sensitization.
Conclusion
This case highlights the importance of cross-reactivity in Hymenoptera venom allergy, with shared allergens such as phospholipases and hyaluronidases playing a critical role. Comprehensive allergenic profiling aids in understanding sensitization patterns and tailoring treatment strategies, including venom immunotherapy.
